Polygenic Inheritance Examples
- Height: There are around 400 genes responsible for the phenotype and environment greatly influences the expression of...
- Eye colour: The colour of the eye is determined by polygenes. At least 9 colours of eye colour are recognised in humans.
What is an example of a non polygenetic trait?
What is an example of a Non-Mendelian trait? Non-Mendelian traits are traits that are not passed down with dominant and recessive alleles from one gene. Examples of polygenic traits are hair color and height. Other traits, such as blood type, show codominance, where there is no dominant or recessive allele.
What does it mean for a trait to be polygenic?
Traits controlled by two or more genes are said to be polygenic traits, which means “having many genes.”. For example, at least three genes are involved in making the reddish-brown pigment in the eyes of fruit flies. Polygenic traits often show a wide range of phenotypes.
What traits are polygenic in humans?
Polygenic traits have many possible phenotypes (physical characteristics) that are determined by interactions among several alleles. Examples of polygenic inheritance in humans include traits such as skin color, eye color, hair color, body shape, height, and weight.
Is skin example of polygenetic trait in humans?
Polygenic traits have many possible phenotypes (physical characteristics) that are determined by interactions among several alleles. Examples of polygenic inheritance in humans include traits such as skin color, eye color, hair color, body shape, height, and weight. Robert M. Kliegman MD, in Nelson Textbook of Pediatrics, 2022.
What are 2 examples of polygenic inheritance?
Some examples of polygenic inheritance are: human skin and eye color; height, weight and inteligence in people; and kernel color of wheat. In fact, kernel color in wheat is nicely shown in Table 2.
Why are some examples of polygenic inheritance?
What are polygenic inheritance examples? Human phenotypes or human physical traits such as hair color, height, skin color, blood pressure, intelligence, autism, and longevity are some of the examples of polygenic inheritance.
What is polygenic inheritance class 12?
Polygenic inheritance is when more than one gene controls a character. It is also known as quantitative inheritance where two or more different pair of alleles which have a cumulative effect on governing quantitative characters.
What is meant by polygenic inheritance?
Polygenic inheritance refers to the inheritance of a trait governed by more than one genes. Generally, three or more genes govern the inheritance of polygenic traits. Multiple independent genes have an additive or similar effect on a single quantitative trait.
What is meant by polygenic?
A polygenic trait is a characteristic, such as height or skin color, that is influenced by two or more genes. Because multiple genes are involved, polygenic traits do not follow the patterns of Mendelian inheritance. Many polygenic traits are also influenced by the environment and are called multifactorial.
What is polygenic inheritance GCSE?
Most characteristics are a result of multiple genes interacting, rather than a single gene. Characteristics that are controlled by more than one gene are described as being polygenic.
Why is human skin color a good example of a polygenic inheritance?
Skin colour is an example of polygenic inheritance, which is controlled by three genes. The darkest colour corresponds to the three dominant alleles (AABBCC) and the lightest skin colour corresponds to the presence of recessive alleles (aabbcc). Rest all the genotype combinations lie in between the two.
Why is human skin color a good example of a polygenic inheritance?
Skin colour is an example of polygenic inheritance, which is controlled by three genes. The darkest colour corresponds to the three dominant alleles (AABBCC) and the lightest skin colour corresponds to the presence of recessive alleles (aabbcc). Rest all the genotype combinations lie in between the two.
Why is eye color a polygenic trait?
It is now clear that eye color is a polygenic trait, meaning it is determined by multiple genes. Among the genes that affect eye color, OCA2 and HERC2 stand out. Both are located on human chromosome 15. The OCA2 gene produces a cell membrane transporter of tyrosine, a precursor of melanin.
Why Is height a good example of polygenic inheritance?
Height is a polygenic trait, it is controlled by at least 3 genes. Individual height varies and has a wide range of possibilities.
How does polygenic inheritance explain why many iris colors are possible?
These traits are known as polygenic traits. The number of genes that determine the color of the iris is unknown, but the most significant of them are found in Chromosome 15 and they are named OCA2 and HERC2. These genes are associated with the production of melanin.
Q.1. What is meant by polygenic inheritance?
Ans: Polygenic inheritance is defined as the quantitative inheritance of multiple independent genes having an additive or cumulative effect on a si...
Q.2. What are the characteristics of polygenic inheritance?
Ans: The characteristics of polygenic inheritance are as follows: 1. Polygenes are the genes that have a minor effect on a phenotype along with the...
Q.3. Which human trait is an example of polygenic inheritance?
Ans: There are many examples of polygenic inheritance in humans like skin and hair colour, height, eye colour, the risk for diseases and resistance...
Q.4. Is blood type an example of polygenic inheritance?
Ans: No, blood type is not an example of polygenic inheritance, rather it is an example of multiple allelism where a single gene has three differen...
Q.5. Who is known as the father of polygenic inheritance?
Ans: Joseph Gottlieb Koleuter is known as the Father of Polygenic Inheritance.
What is meant by polygenic inheritance?
Polygenic inheritance refers to the inheritance of a trait governed by more than one genes. Generally, three or more genes govern the inheritance o...
Which human trait is an example of polygenic inheritance?
In polygenic inheritance, each allele has a cumulative or additive effect on the phenotype thus generating continuous variation, e.g. skin pigmenta...
What are 3 examples of polygenic traits?
Three examples of polygenic traits in humans are height, skin colour and eye colour. These traits are governed by multiple genes.
Is blood type an example of polygenic inheritance?
ABO blood type is an example of multiple allelism, where a single gene has three different alleles or variants (in the same locus) and an individua...
Is eye colour polygenic inheritance?
Yes, eye colour is a polygenic trait. There are two major eye colour genes, OCA2 and HERC2, which are present on chromosome 15. Other than these, t...
Effect of Environment on Polygenic Inheritance
Nature plays a very important role in shaping the characteristics of an individual. Internal or inherent features are also affected by the environment. Usually, the genotype sets the range for a quantitative trait while the phenotype results from the varying environmental factors.
Summary
Polygenic inheritance is defined as the quantitative inheritance of multiple independent genes having an additive or cumulative effect on a single quantitative trait. It is also known as multiple gene inheritance or multiple factor inheritance. It is greatly influenced by environmental factors.
FAQs on Polygenic Inheritance
Q.1. What is meant by polygenic inheritance? Ans: Polygenic inheritance is defined as the quantitative inheritance of multiple independent genes having an additive or cumulative effect on a single quantitative trait. It is also known as multiple gene inheritance or multiple factor inheritance.
What is polygenic inheritance?
“Polygenic inheritance is defined as quantitative inheritance, where multiple independent genes have an additive or similar effect on a single quantitative trait.”. Polygenic inheritance is also known as multiple gene inheritance or multiple factor inheritance.
What are some traits that show polygenic inheritance?
There are many traits in humans, which show polygenic inheritance, e.g. skin and hair colour, height, eye colour, the risk for diseases and resistance, intelligence, blood pressure, bipolar disorder, autism, longevity, etc. Brief description of some of the traits:
What determines the phenotype of a trait?
The genotype sets the range for a quantitative trait, but the environmental conditions decide the phenotype within its genetic limits. Genes function differently in different environmental conditions. Environment regulates the activity of certain genes and sets them on or off.
How does polygenic inheritance differ from multiple alleles?
Polygenic inheritance differs from multiple alleles, as in multiple alleles , three or more alleles are present in the same locus of which any two alleles are present in an organism, e.g. ABO blood group system, which is controlled by three alleles. There is no epistasis involved, i.e. masking of the expression of an allele of the different locus.
How many genes are involved in the expression of phenotype for the length of the corolla?
63 Red (many shades):1 (white) Length of the corolla in tobacco: There are around 5 genes involved in the expression of phenotype for corolla length of tobacco. There is a wide variety in the length of the corolla in tobacco due to polygenic inheritance.
What is a polygene?
Polygene refers to a gene that exerts a slight effect on a phenotype along with other genes. Effect of a single gene is too small, so it is difficult to detect. Multiple genes produce an equal effect. Each allele has a cumulative or additive effect.
How are traits and phenotypic characters present in plants and animals inherited?
Many traits and phenotypic characters present in plants and animals such as height, skin pigmentation, hair and eye colour, milk and egg production are inherited through many alleles present in different loci. This is known as polygenic inheritance.
